Description (adapted form application): The Tissue Culture/Morphology/Xenograph [sic] Transplant Model Core will provide expertise and services in cell culture, intestinal xenografting and various morphologic techniques, including in situ hybridization, immunohistochemistry and microscopy (light, confocal laser scanning and electron microscopy). The service will also serve to consult individual research projects on use of these and related techniques in the planned experiments, especially with regard to the use of human intestinal xenografts as this experimental tool will be utilized in some capacity by all the projects. It will be a major research resource for the projects by providing a centralized cell culture and microscopy facility. As more of the individual projects are using cell biology approaches, the investigators will require an increasing use of cell culture and morphologic techniques. As part of this re-application, we will expand considerably the options in morphology. We will provide expert advice and service in confocal microscopy, using single, double and triple label options, as well as quantitative analysis. We will also provide an expanded fluorescent microscopy capacity including multiple labels, digital photography and quantitative analysis of digital images. The cores also offer training in specific techniques to members of the individual projects and their laboratories and a valuable resource for intellectual and technical interchange regarding scientific and methodological approaches to morphologic probes (quantitative imaging, etc.).